Turkish police say they are investigating whether Khashoggi was murdered in consulate (Reuters)
A senior adviser to Turkish President Recep Tayyip Erdogan said that Turkey has "concrete information" on the abduction of Saudi journalist Jamal Khashoggi.
Turkish authorities suspect that Khashoggi, who disappeared on Tuesday after entering Saudi Arabia's consulate in Istanbul, was killed inside the consulate, Turkish sources told Middle East Eye and news agencies on Saturday.
Erdogan adviser Yasin Aktay, a former MP for Turkey's ruling AK (Justice and Development) party and the man Khashoggi told his fiance to call if he did not emerge from the consulate, voiced concerns over the Saudi nationals whereabouts on Sunday.
Speaking to CNN Turk, Aktay said that Khashoggi's friends had told him to not go to the Saudi embassy and that the consulate was "not safe".
"I am following the issue, and we will inform the world of the outcome of the official probe, which was launched on Saturday"
Turkish President Recep Tayyip Erdogan
"His friends had warned him (Khashoggi), 'Do not go there, it is not safe,' but he said they (the Saudis) could not do anything in Turkey," said Aktay.
"Khashoggi discussed whether to go there with his fiancee beforehand.
"Our security officials are investigating the issue in every detail. We have some concrete information; it won't be an unsolved crime.
"We could determine his entrance but not any exit. That's confirmed. We asked them [the Saudis], they say 'he left,' but there is no such thing on the camera footage.
"That's underestimating Turkey. They are wrong if they think Turkey is as it was in the 90s. The consulate should make a clear statement."
A Turkish source told MEE on Sunday that a forensics team was poised to enter the building.
Aktay's comments came as Erdogan on Sunday said he awaited first results of the investigation into the disappearance of Khashoggi.
Commenting for the first time on the matter, Erdogan told reporters: "I am following the issue, and we will inform the world of the outcome of the official probe, which was launched on Saturday".
"God willing we will not be faced with a situation we do not want."
Erdogan said that he hoped to have the results "very quickly" over the incident involving a "journalist I knew for a long time" and a "friend".
"It is very, very upsetting for us that it happened in our country," he said.
Erdogan said that CCTV footage of entrances and exits at the consulate and the airport in Istanbul were being studied by the police.
A senior Turkish police source told MEE that police believed that Khashoggi was "brutally tortured, killed and cut into pieces" inside the consulate after visiting the building on 2 October.
"Everything was videotaped to prove the mission had been accomplished and the tape was taken out of the country," the source said.
An unidentified Turkish official told the Reuters news agency: "The initial assessment of the Turkish police is that Mr Khashoggi has been killed at the consulate of Saudi Arabia in Istanbul. We believe that the murder was premeditated and the body was subsequently moved out of the consulate."
Aktay said he believed Khashoggi had been killed in the consulate and that Turkish authorities believed a group of 15 Saudi nationals were "most certainly involved" in the matter.
Police said about 15 Saudis, including officials, came to Istanbul on two private flights on Tuesday and were at the consulate at the same time as the journalist. They left again the same day, according to MEE's sources.
Their diplomatic bags could not be opened, a security source told MEE, but Turkish intelligence was sure that Khashoggi's remains were not in them.
An unidentified offical from the Saudi consulate in Istanbul dismissed the claim on Sunday, describing the allegations to the Saudi Press Agency as "baseless".
Khashoggi's fiancee, Hatice Cengiz, said on Twitter she was "waiting for an official confirmation from the Turkish government to believe" the claims.
In his newspaper columns, Khashoggi has been critical of Saudi Crown Prince Mohammed bin Salman's policies and Riyadh's intervention in the war in Yemen.
A legal representative from Khashoggi's family in Saudi Arabia said they trusted Saudi authorities and were cooperating with them, according to Al-Arabiya news.
In a statement on Sunday, Mutasem Khashoggi, the legal adviser to the Khashoggi family in Saudi Arabia, told Al-Arabiya news that he believed external parties were using his brother's disappearance to "push their agenda".